The latest estimated 1-km fissure eruption in the Holuhraun area (north of Bardarbunga) prompted the Icelandic Met Office to raise its aviation warning to the highest level, but there's no reason to believe a repeat of 2010 is imminent.

What happened in 2010?

In April of that year, over 100,000 flights across Europe were cancelled when Iceland’s Eyjafjallajokull volcano spat ash some 30,000ft into the air, creating aviation chaos costing an estimated £1bn/€1.26bn.

What's happening now?

A "small" eruption on (Friday, August 29th saw a 120 nautical mile airspace exclusion zone instigated up to a height of 5,000ft (1,500m). It follows weeks of rumblings that suggest further eruptions are imminent.

That's the big question. Any impact on aviation obviously depends on the scale of the eruption, the ash clouds that result, and prevailing weather conditions at the time.

It's unlikely, however, that a repeat of 2010 is on the cards - even if a substantial eruption does occur.

Since 2010, scientists, the aviation industry, airlines and the European Aviation Safety Agency (EASA) have worked together to review volcanic ash airspace contamination threats. Advanced detection systems and an improved understanding of the risks have lowered the likelihood of widespread airspace closures.

Such closures will now only take place if member states consider volcanic ashes and gases "form a direct threat" for the safety of flight.

Britain's aviation watchdog, the Civil Aviation Authority, has also played down the threat to UK airspace, saying there is no prospect of a blanket grounding of planes following recent activity in Iceland.

Mother Nature, of course, may yet have something to add.

Why are ash clouds dangerous to flights?

Jet aircraft engines can be damaged by volcanic ash.

In 1982, a British Airways Boeing 747 en route from London to Auckland flew into a cloud of volcanic ash thrown up by the eruption of Indonesia's Mount Galunggung, resulting in the failure of all four engines. It glided out of the ash cloud and restarted its engines, safely diverting to Jakarta Airport.

In 1989, aKLM Boeing 747 travelling from Amsterdam to Alaska suffered a failure of all four engines after it flew through a thick cloud of volcanic ash from Mount Redoubt, which had erupted the previous day. The crew tried to restart the engines several times before they were successful, and eventually landed safely.

Who is monitoring the situation in Ireland?

The Irish Aviation Authority (IAA) oversees the safety of Irish airspace, and it follows international guidance on volcanic ash from the International Civil Aviation Organisation (ICAO).

What are Irish airlines saying?

Ryanair: “All flights are operating as normal and we will continue to monitor the situation.”

Aer Lingus: "We continue to monitor the situation closely. There has been no impact on our operations as the airspace we require is unaffected. All Aer Lingus services are operating as normal."

What are my rights if my flight is delayed or cancelled?

If you are booked to fly with a European airline, and your flight is cancelled for any reason, that airline must offer you the choice between:

1) Re-routing as soon as possible, subject to availability, free of charge.

2) Re-routing at a later date.

3) A full refund.

Airlines also have a duty of care to passengers – including the provision of accommodation and food according in certain situations. You can read more on passenger rights here.

Am I covered by my travel insurance?

There was a lot of hand-wringing and frustration in 2010, when passengers found their insurers differing as to whether Eyjafjallajokull was an act of God or a weather event.

Things haven't improved to a satisfying level - it still depends on your policy and your insurer. Just one in four travel insurers covers ash clouds as standard, recent research reveals; others offer 'travel disruption' cover as an extra.